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1/2 number of n X n 0..8 matrices with MM' mod 9 = I.
9

%I #7 Nov 08 2022 11:07:48

%S 1,12,648,419904,3061100160

%N 1/2 number of n X n 0..8 matrices with MM' mod 9 = I.

%F Conjecture: a(n) = 3^(n*(n-1)/2) * A071302(n) for n >= 1. - _Michel Marcus_, Nov 08 2022

%Y Cf. A071302.

%K nonn,more

%O 1,2

%A _R. H. Hardin_, Jun 11 2002